I saw this one today as well, and I loved it. It marched right along and I didn't look at my watch once.
I have to laugh at the negative reviews it's getting because, according to the reviews, the dialogue was bad. This is a disaster movie! People don't go to see it for the sparkling dialogue, at least I don't. I go to see these movies for the disaster stuff, and that was stupendous.
As with all movies, there were parts I just had to hand-wave away...like driving a power boat through water filled with all that debris. I'd think that would do a number on the motor's props, but hey, what do I know. Really, the only time I felt like rolling my eyes was at end with the swelling music and the flag unfurling. Other than that, I had a great time.